Aggressive dual pin track



April 1964 L. ISPEIDEL, JR. ETAL 3,131,002

AGGRESSIVE DUAL PIN TRACK Original Filed April 25, 1961 LOll/S' SPF/05L, JR. EDM ARD 6. 60% JR.

INVENTORS BY 4 fi am ATTUP/VEYS' United States Patent ice 3,131,002 AGGRESSIVE DUAL PIN TRACK Louis Speidel, J12, Royal Oak, and Edward J. Gow, Jr., Oak Park, Mich, assignors to the United States of America as represented by the Secretary of the Army Original application Apr. 25, 1961, Ser. No. 105,524, now Patent No. 3,092,423, dated June 4, 1963. Divided and this application Oct. 18, 1962, Ser. No. 237,424

1 Claim. (Cl. 305-11) (Granted under Title 35, US. Code (1952), sec. 266) The invention described herein may be manufactured and used by or for the Government for governmental purposes, without the payment to us of any royalty there- This application is a division of our original application Serial No. 105,524 filed April 25, 1961, now issued as US. Patent No. 3,092,423 dated June 4, 1963, for Aggressive Dual Pin Track.

This invention relates to a track for track-laying vehicles.

More particularly, the object of our invention is to provide a connecting pin arrangement which results in a greater portion of a given track shoe width being used for grouser. Specifically, this arrangement entails the use of dual axially separated track pins in lieu of the prior art single pin connector whose length thereof is longer than the composite length of the dual track pins. The use of dual pins enables volume previously occupied by the long single pin connector and its associated bosses to be utilized as a trap for soil which would not have ordinarily entered between the track shoes. The additional soil entrapped between adjacent shoes serves to greatly increase the traction between track and ground and insures aggressiveness of the track in all types of terrain.

-A further object of our invention is to provide track pins for use with a track-laying vehicle that results in a track with no decrease in ability to absorb tensile stresses but with a high degree of grousing ability due to the small amount of space occupied by our pins.

A further object of our invention is to provide a pin arrangement that will result in easier pin installation and removal. The installation and removal of the prior art single pin connector is difficult due to the fact that such a pin must pass through up to five bosses in order to connect or disconnect adjacent track shoes of a given width. This means a great deal of friction must be overcome in order to install or remove a single pin connector. Further, the removal of a single pin connector, bent by diiferential movement of the bosses, may be very diflicult. The use of our dual pin arrangement with adjacent track shoes of the above width greatly relieves or eliminates the above difiiculties since it is necessary for each pin of the dual pin arrangement to pass through only two bosses.

With the foregoing and other objects in view, the invention resides in the novel arrangement and combination of parts and in the details of construction hereinafter described and claimed, it being understood that changes in the precise embodiment of the invention herein disclosed may be made within the scope of what is claimed without departing from the spirit of the invention.

In the drawings:

FIG. 1 is a plan view of two connected track shoes utilizing our connecting pin arrangement.

FIG. 2 is a perspective view of the track shoes illusrated in FIG. 1.

FIG. 3 is an elevational view of our connecting pin engaging adjacent track shoes with portions of the pin and track shoes being shown in section.

Referring now specifically to the drawings, FIG. 1

3,131,002 Patented Apr. 28, 1964 illustrates two track shoes of an endless track utilizing our connecting pin arrangement. The use of our dual connecting pins (contained within bosses 2 and 4) enables volumes 6, 8 and 10, previously occupied by the prior art single pin connector and associated bosses to be utilized as a trap for soil which would not have ordinarily entered between track shoes 12 and 14. This additional soil entrapped between ground contacting track shoes serves to greatly increase the traction between the track-laying vehicle and ground and insures aggressiveness of the vehicle in all types of terrain.

Although FIG. 1 shows specific details of the track shoe body (the portion of the track shoe with the exclusion of the pins and bosses), it is not per se to be considered part of the invention, and it is to be understood that this invention is not limited to use with a specific track shoe body but is to be considered equally useful with shoes of different designs.

Referring to FIG. 3, there is illustrated our dual axially separated track pins 16 engaging adjacent track shoes 12 and 14. The pin 16 is provided with a weight reducing recess 18 at one end and athreaded opening 20 at its opposite end. Bolt 22 with head 24 is threaded through opening 26 in boss 4 and engages the pin by being received in opening 20. The pin is made up of journal 28, cylindrical segment 30, a tapered portion 32 connecting the ends of the cylindrical segment and the journal, and knurls 34 provided on the cylindrical segment. The surfaces of all the above parts are designed to engage and mate with internal portions provided in first bearing boss 2 and second bearing boss 4, it being understood that a key and keyway could be substituted for knurls 30 if so desired.

The connection of track shoes 12 and 14 is accomplished by drawing pin 16 into boss 4 by the turning of bolt head 24. As the pin moves into boss 4, its body portion is pulled into engagement with the internal taper and knurls of boss 4. When bolt 22 can no longer be turned, pin 16 has been drawn into tight engagement with boss 4. Pin 16 is now positively fixed within the boss and cannot be removed until the bolt is reversed and removed.

As seen from FIG. 3, pin 16 is positively fixed to track shoe 14 and journaled to track shoe 12 through journal 28. The tensile load on journal 28 is transmitted to hearing boss 2 through the bearing 44 which is press fitted within boss 2. Bearing 44 is preferably made from a material such as Teflon or Oilite, which are both widely used for lubricating bearings. The bearing boss cavity (and bearing therein) are protected from weathering by providing a self-locking threaded plug 36 on its outer end and a sealing ring 38 on its inner end. The plug 36 is provided with a recess 40 adapted to receive a tool which can loosen or tighten the plug in its seat.

Sealing ring 38 is preferably made from natural or synthetic rubber and is also press fitted within boss 2. A metal ring 42 made from a beryllium-copper alloy is joined to the inner surface of sealing ring 38 so that it is in continuous engagement with journal 28. This metal ring eliminates the friction and wear that would occur if the rubber seal 38 directly engaged journal 28. It is noted that our dual pin arrangement requires the use of only two sealing rings of the type described above for a connection between two track shoes while a track shoe connection using the single pin connector may require many more since the pin passes completely through each boss.

An alternative to the use of bolt 22 as means to draw pin member 16 into boss 4, a threaded stud may be formed on the pin. After the stud is passed through boss 4, the pin is drawn into the boss by threading a nut on the projecting stud.

a a The structure described above results in providing reduction of seal points to one for each pin, ease of installation and removal of the pin, and a track shoe with a minimum of 40 percent of its Width being used for full aggressive grouser. We claim: An endless track embodying articulated track shoes, each shoe comprising first and second longitudinal sides,

a pair of spaced first bearing bosses each formed with a cavity therein being integrally formed on said first longitudinal side, a pair of spaced second bearing bosses each formed with a cavity therein being integrally formed on said second longitudinal side, means pivotally connecting said first pair of bosses on a first shoe to said second pair of bosses on a second shoe, said means formed by spaced track pins, each pin defined by a central tapered body member having a cylindrical journal portion extending from the base of said body member and a cylindrical segment portion extending from the tapered end of said body member, each of said second bearing'bosses having their associated cavity partially tapered and partially cylindrical to receive the tapered body member and cylindrical segment portion of each pin, each of said first bearing bosses being formed to completely cover the journal portion of said pin, sealing means disposed in the cavity of each of said first bearing bosses between each said pin and its respective first bearing boss to completely seal the end of said pin Within the confines of said first bearing boss, said track pins having knurls on said cylindrical segment adjacent said body member corresponding to internal knurls formed within said second bearing bosses, a bolt inserted through the closed end of said second bearing bosses and threadably connected to said cylindrical segment end of said pin whereby said knurls on said track pins are detachably drawn into engagement with said internal knurls of said second bearing bosses, said engaged first and second bearing bosses and pins occupying a volume that insures a minimum of 40% of said first longitudinal side being used for full aggressive grousing.

References Cited in the file of this patent UNITED STATES PATENTS 1,494,568 Allen May 20, 1924 1,956,580 Knox May 1, 1934 2,061,223 Cunningham et al Nov. 17, 1936 2,264,135 Kaminsky Nov. 25, 1941 

